The present invention relates a sensor for automatic release of occupant protective devices in the event of an accident.
It is known to use a sensor of the above mentioned general type in which an undampened pendulum is provided for determination of vertical deviations and translatory acceleration. During normal traveling operation of a power vehicle, only translatory accelerations take place which are smaller than the ground acceleration, for example adhesive friction of the tires. Thereby, the pendulum indicates maximum deviation from a vertical of 45.degree. . In traveling conditions of the power vehicles which lead without rotation to greater deviations, for example in the event of crash accident or travel over a curve while the vehicle is guided by a guiding bar, the occupant safety devices must be released without breakdown occurring. The undampened pendulum, however, exhibits with respect to an outside excitement the suspension of an oscillatory system. As a result of this, the sensor even in non-critical traveling conditions, for example slalom travel, can release the occupant safety devices.
Furthermore, the pendulum can be suspended also in a closed chamber which is filled with a damping liquid. Therefore, it is possible to dampen the pendulum critically, However, its upper limiting frequency with respect to the rotation and translation is reduced, so that the sensor with a technically possibly pendulum length possesses too long reaction time. This is, however, a critical selection criteria with respect to occupant safety devices. What is really required is that the sensor reacts as fast and as delay-free as possible, and the occupant safety devices are released in the event of the accident at the proper time.